Insulator-support thimble



G. T. SOUTHGATE.

INSULATOR SUPPORT THIMBLE.

APPLICATION FILED OCT. 20, 1915.

Patented Sept. 16, 1919.

GEORGE T. SOUTHGATE, 0F BROOKLYN, NEW YORK.

IIISULATOBr-SUPPORT THIMBLE' Specification of Letters Patent. PatentedSept. 16, 1919.

Application filed October 20, 1918. Serial No. 128,791.

To all whom it may concern:

Be it known that I, Gnoncn T. Sou'rrIGA'rE, a. citizen of the UnitedStates, resldlng at Brooklyn, in the county of Kings and State of NewYork, have invented certain new and useful Improvements inInsulator-Support Thimbles; and I do hereby declare the following to bea full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same.

My invention relates to insulator support thimbles. One object of myinvention is to produce a metallic thimble capable of being mounted upona hollow or solid cylindrical .pin or upon a pin C-shaped in crosssection.

A further object of my invention is to shape the exterior and interiorsurfaces of said thimble so that the interior surface shall be rigidlysupported by said pin when undue stresses are applied to the exterior ofsaid thimble; and so that the exterior surface of said thimble shall atall times fit snugly in the usual screw thread of glass or porcelaininsulators.

A further object of my invention is to so shape my improved thimble thatvery thin metal can be used in its formation. By the use of such metalthe elements of the outer surface of said thimble have considerableresiliency, whereby a more perfect fit is obtained between the thimbleand the screw threads in said insulators.

A further object of my invention is to provide a large and firm slidingsupport for the upper end of the thimble upon the body of the pin. Bythis means I provide that as the body of the thimble is compressed tovarying degrees, owing to the irregularity of the screw threads on theinterior of said insulators, that the upper end of the thimble is guidedby the pin but is free to move up Or down. This provision also allowsfor variationsv due to thermal expansion and contraction.

A further object of my invention is to provide a resilient top for myimproved thimble which will insure a resilient contact of the same withthe top of the threaded hole in the insulator, thus avoiding anyexcessive mechanical stresses should excessive force be applied to theinsulator when it is screwed upon the thimble, and also insuring thatthe outer surface of the thimble will be forced into firmer contact withthe threads in said insulators. I

A further object of my invention is to provide such a thimble capableof' being formed from a single piece of metal by the factor operationsof blanking and forming, and the field operations of mounting thethimble upon a in and securing it thereto.

A further obJect of my invention is to provide a thimble thatcan bereadily galvanized after the forming operation is completed whereby theabsence of cracks in the zinc coating is insured.

In the drawings Figure 1- is an elevation of my improved thimble asapplied to a C-shapedpin, the lower portion of said pin being shapedinto the form of a bracket for direct attachment to a pole or building;

Fig. 2 is a cross section along the line 22. of the parts shown in Fig.1 looking in the direction of the arrows.

. Figs. 3 and 4: are respectively plan and sideviews of my improvedthimble shown in Figs. 1 and 2 before the same is bent into anapproximately U-shape.

Fig. 5 is a side view of a variation of .my improved thimble.

Fig. 6 is a view of the thimble shown in Fig. 5 looking in the directionof the arrow 6 in said figure.

Fig. 7 is a fragmentary view showing the means by which the thimble issecured to the pin.

In the drawings, 10 is a pin which may be formed of sheet metal,C-shaped in cross section as shown in Figs. 1 and 2 and provided with abracket 11 formed integrally therewith for the purposeof securing thepin 10 to a pole orbuilding.'

The in 10 may be formed of a tube, or it may e solid, the requisitesbeing that the outer surface thereof shall be approximately cylindricalat its lower portion and the right frustum of a cone at itsupper'portion. The

characteristics to suit the work the thimble is to be employed.

desired chemical constitution and, physical-.

for which.

After the blank is cut, I then form the blank into the shape shown inFigs; 3 and 4, wherein 12 is a portion shaped approximately to. thesurface of a sphere and on each side thereof two exactly similarthreaded portions 1313 are provided.

Each of the portions 1313 is provided with a plurality of screw threads14, said threads having such relative sizes that when the thimble ismounted upon the pin, as hereinafter described, said threads fit thethreads in the interior of the insulator in which it is to be used. 1

Between each threaded portion 13 and the spherical portion 12, there isprovided a portion 15 forming approximately the frustum of a cone for apurpose hereinafter explained.

Each threaded portion 13 has formed on .its outer end a. cylindricalportion 16 which terminates in a flange 17. A second cylindrical portion18 extends outwardly from the flange 17. The portion 18 is joined to thebead 18 and a third cylindrical portion 18 is joined to the bead 18".The threaded portions 13 are provided with slots such as 20 inorder toincrease the resiliency of the screw threads 14.

After the blanlr for my improved thimble has been formed as justdescribed, it is to be bent along the lines 2222', see Figs. 3 and 4,until the inner surface of the cylindrical portions 1818 and 1818 are inposition to closely embrace the correspondin ly shaped portion of thepin 10.

The b ending just described can be erformed either in the factory or inthe eld when the thimble is to be applied to the pin 10, but in any caseafter the thimble is mounted upon the pin 10, the inside surface of thebead 18 fits closely around the outside surface of the head 10 on thepin 10.

The inner surface of the portion 15 of the thimble will bear upon theupper cone shaped portion of the pin 10, and the inside of the threads14 will'be just out of contact with the conical portion of said pin. Byreference to Fig. :1 it will also be noted that the top 12 of myimproved thimble will be above the top of'the pin 10.

If now an insulator is screwed upon the threads 14, the same will befree to compress and the slots 20 will insure that the two sections ofeach half portion of in improved thimble can be moved indepen ently ofeach other, hence it is evident that the threads 14 will produce ayielding pressure upon the threads of the insulator, thus insuring thatthe same can be securely mounted upon the thimble and obviating anydanger of the insulator being broken during this operation,

wardly tion, a vurved top,

be screwed down ex- 12 of my improved end of the hole in the connectionof said top with the portions 15 of my improved thimble, said portions15 and the adjacent threads 14 will be forced outwardly and the latterwill securely grip the threaded portion of the insulator.

.lDuring changes of temperature it is evident that the head 12 can bemoved upor downwardly without any undue stress owing to the fact that itis not secured to the pin 10. Should undue stress come upon the spans ofwire attached to the insulator mounted upon my improved thinllole, thethreaded portion 13 will move slightly sidewise until the interiorportion of the threads 14 come into firmcontact with the pin 10.

in the variation of my improved thimble shown in Figs. 5 and 6, I formsaid thimble from either a tube or a plate by a pressing, rolling orspinningprocessa The top 12* of said thimble is formed by bending theend over. I also provide a plurality of slots such as 12) in tion 13- isprovided with threads 14 in all respects similar to the threads 14 shownin There is also a portion l5 forming the frustum of a cone andextending between the portion 13 and the top 12. The cylindrical, orfrusto-conical portion 16 is formed on the lower end of the portion 13*.Said cylindrical or frusto-conical portion terminates in a flange 17 anda cylindrical, or frusto-conical portion ISprovided with a bead 18 isjoined with the flange 17. Four slots 20 are provided in the portion 13for said end. The body por' give slightly; At the the purpose ofrendering the threads 14 resilient. A plurality of slots, such as 18 areprovided in the frusto-conical por tion 18*. V

The thimble shown in Figs; 5 and 6 is mounted upon a pin similar 'to 10in the same manner as the thimble shown in the other figures and itsmodeof operation is similar to the mode of operation of said thimble,excepting that when the thimble is applied to the pinthe slots 18 permitthe frusto-conical portion 18 to spring outwardly so that the bead 18may embrace the bead 10 ofothe pin.

at I claim is j 1. A metallic thimble formed of a single piece of sheetmetal, and provided with a threaded portion, an upper tapering poralower cylindrical portion and slots in said threaded, tapering andcylindrical portions, in combination with a pin having a tapering endembraced by said tapering portion and a cylindrical body embraced by thecylindrical portion of said thimble.

2-. A metallic thinible formed of a single piece of sheet metal, andprovided with a threaded portion, an upper tapering portion, a curvedtop, and with a lower cylindrical portion provided with a bead, incombination with a pin havin a bead embraced by the head on said thimle.

3. The combination with a pin, of a metallic thimble formed ofdiametrically opposed portions joined together at their tops andseparated at their bottoms, said portions being secured at their bottomsto said pin and having a sliding bearing thereon near theirto s.

n testimony whereof I affix my signature.

GEO. T. SOUTHGATE.

